Influence of Interplay of Volume and Interface Spin Transfer Torques Affecting Current Induced Domain Wall Transport in Atomically Engineered Multilayered Racetracks

Advances in our understanding of the current controlled motion of domain walls in perpendicularly magnetized multilayer stacks has led to very high domain wall velocities. The motion is controlled by several spin orbit derived phenomena including, notably, the Spin Hall Effect, and the Dzyaloshinskii-Moriya interaction. Here we study atomically engineered multilayered racetracks in which interface and volume derived spin transfer torques compete with each other. Of especial significance is the dependence of the domain wall motion on the magnitude and direction of in plane magnetic fields that compete with the Dzyaloshinskii-Moriya exchange fields. The various contributions to the interface and volume torques are independently varied to allow their respective contributions to be separated. Insight is provided by 1-D analytical modeling of the domain wall motion to extract relevant parameters.